Public vulnerability disclosure

CVE-2026-125331

HarnessRouter: Service-only routes that write an organization's provider connections could be reached through a multi-tenant console with a made-up bearer

publishedCWE-862CWE-863

HarnessRouter is a self-hosted unified API for running agent harnesses with sessions, streaming, files, cancellation, and failure handling. Prior to 0.31.8, a console that is not in self-hosted mode attaches the server's internal key to requests carrying an Authorization header before validating the bearer, while the service-only PUT and GET /v1/orgs/{org}/connections/{name}, PUT /v1/orgs/{org}/policy/{backend}, and /internal/* routes trust that key and take the organization from the URL. In a multi-organization deployment, a remote caller can use a made-up bearer to rewrite another organization's provider connection to an attacker-controlled endpoint, causing later prompts to be disclosed and attacker-controlled responses to influence tasks. This issue is fixed in version 0.31.8.

Technical severity9.1 criticalCVSS 3.1 · CNA: GitHub_M
Published2026-11-10Source updated 2026-11-12
Collected2026-11-123 attributed sources

Fixes and workarounds

No remediation reported in collected sources.

Missing remediation information is not evidence that no patch exists.

Affected products and versions

Affected products, source version ranges and reporting authorities
ProductVersionsAuthority
harnessrouter
HarnessRouter
< 0.31.8 (affected) CNA: GitHub_M

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / scoreVectorAuthority
3.1 / 9.1
critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NCNA: GitHub_M
3.1 / 9.1
critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NNVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

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